
1
1
Introduction
1.1 Ordinal Variables versus Ordinal Models
Social and behavioral scientists often analyze ordinal outcomes, which are variables with
categories ranked from low to high on a single dimension or characteristic. However,
the distances between categories are unknown. For example, the General Social Survey
(GSS) includes a measure of attitudes toward same-sex marriage based on the follow-
ing question: “Do you agree or disagree … homosexual couples should have the right
to marry one another.” The response options are based on a Likert scale: 1 = strongly
disagree, 2= disagree, 3 = neither agree nor disagree, 4 = agree, and 5 = st ...